Ancestral property sell tax

SUSANTA ADHIKARY (1 Points)

29 November 2023  

My father has given his old ancestral property to a builder to develop a small 4 storied apartment on 50-50 partnership. He received 2 flats and sold one , while staying at the other one. He spent some money on the newer apartment (interior + transfer of property from siblings using a gift deed). 
How can he save capital gain tax for the sold property?